Share internet bandwidth from HQ to branch?

Hi everyone,

Like to check on this possibility.

Let's say I have this.

HQ - 50MB dedicated line
Branch - 10MB DSL line (not dedicated but go through few hops)

Now both HQ and Branch are connected via IPSec Site-to-Site VPN.

Could I allow Branch to take advantage of the HQ internet speed? Means instead of using the branch 10MB (which the 10MB is just a meant for communication to HQ), now branch can use 50MB internet speed (or probably 20 - 30MB).

Some people said can have WAN compressions and somehow ways to boost up the throughputs.

Is this even possible? Any open source solution which can do the above? Or the paid ones?

Any help? Thanks in advance.